Clarification of milk.



B. R. WRIGHT.

CLARIFICATION 0P MILK.

APPLICATION FILED JULY 21, 1913.

Patellted Dec. 29,1914.

2 SHEETS-SHEET l.

- llvvdvro WZ/Q d By v I ATTORIVEY8 WITNESSES 4 fl I B. R. WRIGHT.

GLARIFICATION 01-" MILK.

APPLICATION FILED JULY 21, 1913.

1,122,457, Patented Dec. 29, 1914.

2 $HEBTS-SHEET 2.

INVENTOR A TTOR/VEYS orrrcn I BERT R. WRIGHT, 0F POUGHKEEPSIE, NEW YORK,ASSIGNOR TO THE DE LAVAL SEPA- RATOR COMPANY, OF NEW YORK, N. Y., ACORPORATION- OF NEW JERSEY. 1

Application filed July 21, 1913. Serial No. 780,326.

To all whom it may concern:

Be it known that I, BERT R. \VRIGHT, a citizen of the United States,residing at Poughkeepsie, county of Dutchess, State of Xevv York, haveinvented certain new and useful Improvements in Clarification of Milk;and I do hereby declare the following to be a full, clear, and exactdescription of the invention, such as will enable others skilled in theart to which it appertains to make and use the same.

This invention relates to the centrifugal clarification of milk and hasfor its object the removal of the objectionable matter, such asinflammatory discharges, dirt, and other inherent and foreignsubstances, which are commonly found in milk, (whether in the milk as itcomes from the cow or gotten into it through milking or in handling),without separating or otherwise afiecting the normal distribution of thebutter-fat globules in the milk and their relation to the other milkconstituents; so that the resultant product of the operation shall bemilk, containing its normal content of butter-fat normally distributedtherethrough, practically devoid of solid impurities and otherobjectionable matter, with a substantial reduction in bacterial contentand a diminished tendency to bacterial development, particularly ofharmful character.

The invention hereinv described is essen- 1 tially different and incertain important respects substantially the reverse of the operationspractised in any previously attempted centrifugal clarification of milk.

Heretofore all efforts to centrifugally clarify milk have, by reason ofthe construction employed, necessarily involved separation, to at leasta considerable degree, of the so-called cream and skim-milk or heavierand lighter parts of the milk, and the remixing of the cream andskim-milk. In such circumstances the remixing of the buttor-fat globulesand other parts of milk is not uniform, and where the butter-fatglobules have been once partially separated and brought together more orless in clusters, by which their relative buoyancy to the other parts ofmilk is increased, they thereafter rise more freely and separate morecompletely from the other parts of milk than they would naturally, sothat in the case CLARIFICATI'ON 0F MILK.

Patented Dec. 29, 1914.

of milk of which the clarification has been attempted in such manner andwhich is then placed in cans or bottles the cream rises differently andpresents a different appearance than ordinarily in the case ofunclarified milk. The cream at the top of the can or bottle will bedenser and of less bulk or quantity. The line of demarcation between thecream and skim-milk is more clearly defined and the skim-milk is bluerand more watery in appearance, which conditions make an unfavorableimpression on the average buyer and constitute serious commercialdisadvantages in the marketing of the milk. These diflicultiesheretofore have' been mainly due to the employment of types ofconstruction primarily intended for centrifugal cream separation, whichconstruction not only permit-ted but facilitated and was primarilydesigned to accomplish the separation of the heavier and lighter fluidparts of the milk, and with which the degree of clarification possiblewith such a bowl has been merely an incidental result.

In the present invention it has been recognized that it is quite asimportant to prevent separation as to effect clarification, and thesemay be said to be its two-fold and parallel purposes, though each isaccomplished substantially independent of the other,-that isclarification without separation and clarification more completely thanever b fore.

In the case of all previous types of construction the delivery of themilk into the free space of the bowl has been at a point not near enoughto the periphery to sub ect all of it to a maximum, or sufficient,degree of centrifugal force for complete clarification, since themovement of the lighter parts of the milk from such point of delivery tothe free space of the bowl has been at once inward toward the center, orto the line of discharge from the bowl. At the same time, with suchconstruction, where more or less separation of the heavier and lighterparts of milk necessarily occurs, the movement of the heavier fluidparts is outward in the same direction as the objectionable matter ofwhich it is desired to clarify 1t, whlch removal is rendered moredifiicult by the course of each being in the same direction, as well asby the fact that the heavier parts of m1lk being of more nearly likespecific gravity to the dirt and other foreign matter this heavierliquid is not as easily clarified as would be the whole milk and much ofthe impure matter is not removed from it. Again, where construction ofthe ordinary cream separator type has been employed in clarification thedirt or objectionable matter holding space at the periphery is alwayslimited in depth and the construction of the' bowl throughout isnecessarily of such charaster that after a comparatively short durationof run much of the matter that may once have been removed from the milkand deposited against the periphery is again caught up andcarried off bythe rapidly moving currents of heavier or skim-milk parts, first outwardtoward the periphery and then upward'or downward through the peripheralspace to the point of discharge.

In the operation of the apparatus herein .described the movement of thewhole milk, both its lighter and heavier fluid parts, is always in onedirection, whatever this may be, and so controlled as to afford noopportunity for division or separation, while at the same time, as hasbeen said, the whole milk is subject to the maximum degree ofcentrifugal clarifying force. The movement of the whole milk from thecentral inlet chamber is first outward to the annular near-peripheralspace, through restricted passages and at such velocity as to preventseparation. The full mass of milk is subjected to the clarifying forcein this near to the periphery annular space, the depth of which is ampleto permit of the deposit of all matter of which the milk may be clarified. Thence the movement of the whole milk is inward toward the centerof the bowl, and the inward movement controlled by the use of a diskliner or equivalent means of dividing the milk into thin sheets, whichat the same time completes its clarification,

, heavier parts of the liquid, or rather of the heavier portion to lagbehind the lighter portion, one measure of butter-fat globules orfighter portion of liquid merely replaces another such lighter portionin a heavier portion, without changing the relative distribution ofbutter-fat globules or the normal proportion of the lighter and heavierparts of the milk, and entirely without separation of them.

Many experiments as well as much practical use of my invention havedemonstrated that there is no discernible change in the distribution ofbutter-fat globules in the clarified milk product resulting from its theuse of my invention the necessary pracr tica-l conditions are realizedfor obtaining a maximum centrifugally clarifying action on milk withoutany substantial disturbance of the normal relationship existing betweenthe butter-fat globules and other milk parts or constituents, and theclarified milk cannot be distinguished from that which has'not beencentrifugalized, except for its desired freedom from sediment,objectionable foreign matter and lessened bacterial content, whichlatter consideration, especially as regards harmful and disease breedingbacteria, the experiments thus far made and now proceeding indicate tobe of very great importance.

In the accompanying drawings,Figure 1 represents, in section, aclarifier adapted for the practice of the invention; the outer casingbeing shown as broken away; Fig. 2 represents a section. on a planeindicated by the line 22 of Fig. 1; Fig. 3 represents a bottom plan viewof the feed sleeve constituting one of the elements of the clarifier;

Fig. 4 represents a'section on a plane indi cated by the line -f14: ofFig. 1.

Similar numerals of reference indicate similar parts throughout theseveral views. Beferringto the drawings, 1 represents the outerstationary casing of the clarifier,

having the customary pedestal 2. The bowl of the clarifier consists ofan outer shell 3, having an upwardly projecting frusto-conical bottom &,and a hollow taper stem 5, with a conical top, said stem rising from thecenter of the bottom. The cavity of the stem is hemispherical at itsupper end and is provided with a cross pin 6. The pin fits within andengages a slot 7 in the hemispherical upper end of a shaft 8, whichsupports and carries the bowl. On the outside of the .stem 5 is a sleeve23 provided with ribs 9 having channels between them.

Surrounding thesleeye 23 and guided by the ribs 9 is asleeve 10 whichextends upwardly to the top of the bowl and forms a centralinletchamber, within which are vertical ribs 11. ward extension 12surrounding the upper portion of the frusto-conica-l bottom ,4 of thebowl. In the underside of this downward extension 12 of the sleeve arerestricted passages 13, tangential to the lower part of the centralinlet chamber of the sleeve. The lower outer ends of these passages 13open directly into the peripheral space 1 The tubular portion of thesleeve has outer ribs 15 between which are channels for the upward flowof the liquid toward the dis charge from the bowl.

Guided by the ribs 15 is a series of frusto This sleeve also has adownconical disks 16, which have radial ribs 17 on their upper sides tospace themthe proper distance apart. The bottom disk of the series isprovided further with ribs on its lower side, to space it at a properdistance fromthe conical downward extension 12 on which it rests. I

The top 18 of the bowl rests on the uppermost disk of the series and,when drawn to the shell 3 by means of the coupling ring 19,v serves toclamp all of the disks together,

forcing them down on top of the sleeve extension 12, and, in turn, holdsthe sleeve against the frusto-conical bottom of the bowl.

It will be noted that the maximum diameter of the sleeve-extension aswell as that of the disks is considerably less than the inside diameterof the bowl, thus leaving an ample peripheral clarifying andslime-holding space 14. A rubber ring 20, which, when the top 18 isdrawn down by the coupling ring 19, is tightly clamped between the topand the shell, serves to prevent leakage. A nut 21 when screwed downagainst a shoulder on the sleeve 10, leaves between it and the neck 22,a discharge orifice for the clarified liquid.

The milk to be clarified is fed to a cup, not shown, above the machine,and passes through a feed tube extending downward within the upperportion of the sleeve 10. The stream from this tube strikes the conicaltop of the stem 5 and is deflected outward against the inside of thesleeve where it is caught by the ribs 11 and is caused to rotate withthe bowl. It then passes at high velocity downward through the channelsbetween the ribs 9 and 'outward through the ,restricted channels 13 tothe peripheral space 14,.where all of the liquid is subjected to themaximum centrifugal force. From the peripheral space 14, the liquidenters the narrow passages left between the disks 16 by the ribs 17 onsaid disks, and traverses them tothe channels between the ribs 15 on thecentral sleeve 10, through which channels it passes upwardly to thedischarge orificenover the neck 22 of the bowl top 18.

, The central inlet or milk-receiving and distributing chamber lieswithin the discharge from the bowl, so that there is no tendency oropportunity for separation of the butter fat from themilk in saidchamber, nor can either of the liquid constituents lag in the restrictedpassages leading therefrom. v

It will, of course, be understood that the clarifier is to be driven atthe high velocity customary in centrifugalizing milk, varying, as iswell known, according to the diameter of bowl or revolving vesselemployed. In establishing the cross-sectional area of the channelsleading outwardly from the central inlet chamber to the anpassingthrough them to avoid separation of the butter globubles from the otherparts of the milk. The annular peripheral space should be of suchrelative size, as indicated for instance in the drawings, as to provideample room for the deposit and accumulation of the matter removed fromthe milk.

It will be understood that in this specification. in referring to theproduct to be clarified as milk, I intend the term to be construed inits generic sense, that is to say as an emulsion wherein the proportionof butter fat globules present as one of the constitutents of thecompound fluid may vary within wide limits,the purpose being to passthrough the machine. the milk fluids them therefrom clarified andunseparated in whatever proportions they may be combined as subjected toclarification.

Having thus described my invention, what I claim is:

1. The method of clarifying milk, which comprises propelling the liquidfrom the center of .a revolving bowl to a peripheral space whereimpurities heavier than milk are deposited. and thence inwardly towardthe center of the bowl and point of discharge therefrom. and restrictingthe flow of the milk to and from the peripheral space to streams ofsmall cross-sectional area, whereby clarification is efi'ected andseparation of the heavier and lighter liquid constituents of the milk isprevented; substantially as described.

2. The method of clarifying milk, which comprises delivering the milkcentrally within a revolving bowl, restricting the flow of the milktoward the periphery to' streams of small cross-sectional area,conducting the milk through a peripheral space, where impurities heavierthan milk are deposited, and then directing the flow of the milk towardtheaxis of the bowl in multiple thin sheetlike streams. and thence to adischarge, whereby clarification is effected and separation of theheavier and lighter liquid constituents of the milk is prevented;substantially as described.

3. The method of clarifying milk, Which comprises delivering the milkcentrallywithin a revolving bowl, restricting the flow of the milktoward the periphery to streams of small cross-sectional area,conducting the milk through a peripheral'space, where impurities heavierthan milk are deposited, and then directing the flow of the milk towardthe axis of the bowl in multiple thin radially subdivided sheet-likestreams, and thence to a discharge, whereby clarification 4. The methodof clarifying milk, which comprises propelling the milk from the centerof a revolving bowl to 'a peripheral space where impurities heavier thanmilk are deposited and thence inwardly toward the center of the bowl andport of discharge therefrom, and causing the heavier and lighter liquidconstituents of the milk to move in the same direction both outwardlytoward the peripheral space and inwardly therefrom to the port ofdischarge at such rate and volume of current flow as to deliver the milkfrom the bowl without substantially changing the distribution of thebutter fat globules therein; substantially as described.

5. A- centrifugal milk clarifier, comprising a rotating bowl having acentrally disposed inlet consisting of a milk-receiving and distributingchamber lying within the discharge from the bowl and havingrestrictedpassages lead-ing therefrom to an annular peripheral"clarifying and dirt-holding space, where impurities heavief than milkare deposited, means for directing the flow of the milk from theperipheral space toward the center of the bowl in streams of smallcross-sectional area,iand a discharge outlet for the milk; substantiallyas described.

6. A centrifugal milk clarifier, comprising a rotating bowl having acentrally disposed inlet consisting'of a milk-receiving and distributingchamber lying within the discharge from the bowl and having restrictedpassages leading therefrom to an annular peripheral clarifying anddirt-holding space,

means? where impurities heavier than milk arede' posited, means fordirecting the flow of the milk from the peripheral space toward thecenter of the bowl in multiple thin sheet-like streams, and a dischargeoutlet for the milk; substantially as described. 1

7. A centrifugal milk clarifier comprising a rotating bowl having acentrally disposed inlet consisting of a milk-receiving and distributingchamber lying within the discharge from the bowl and having restrictedpassages leading therefrom to an annular peripheral clarifying anddirtholding space, where impurities heavier than milk are deposited,means for directing the fiow of the milk from the peripheral spacetoward the center of the bowl in multiple thin radially sub-dividedsheet-like streams, and a discharge outlet for the milk; substantiallyas described.

v8. A centrifugal milk clarifier, comprising a rotating bowl having acentrally disposed inlet consisting of a milk-receiving and distributingchamber lying within the discharge from the bowl and having restricted.

passages leading rearwardlytherefrom to an annular peripheral clarifyingand dirtholding space where impurities heavier than milk are depositedmeans for directing the flow of the milk from the peripheral spacetoward the center of the bowl in streams of small cross-sectional area,and a discharge outlet for the milk, substantially as described. v 4

In testimony whereof ll afix my signature, in presence of two witnesses.

BERT 1R. WRIGHT.

Witnesses:

S. B. Roomrnmnn,

W. A. HUBBARD.

